Installation, commissioning and operating instructions

The following figure (refer to fig. 7–10 ) depicts dependency of cycle life on depth of discharge and tempera- ture.

Depth of discharge (DoD) in %

Fig. 7–10: Cycle lifetime of OPzS solar power depending on DoD and temperature

7.10.3 Electrolyte freezing point depending on depth of discharge (DoD)

The freezing point of the electrolyte (sulfuric acid) rises with increasing depth of discharge.

In case the battery is exposed to cold ambient temperatures (< -5°C) the maximum depth of discharge has to be decreased in order to avoid electrolyte freezing and potential damages of the cell jar. Fig. 7–11 shows an example for this relation. Example: If depth of discharge is below 60% the operating temperature must not be below -18.4 °C.

Depth of discharge (DoD)

Fig. 7–11: Electrolyte freezing point as a function of depth of discharge (DoD)

Installation, commissioning and operating instructions for vented stationary lead-acid batteries

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